So tonight, while at band practice, guess which amp blew...

[mightywarlock]

you asked about the Deuce II?

all those questions people ask about sound differences and such...well...i don't know what to make of them now.

The Deuce II and the Ace, while sounding closely the same, are night and day difference, but that may also be somewhat Cabinet choice.(no real choice on the Ace Combo).
I called Mesa before i bought the Deuce as well, and asked the same questions and they told me the Deuce, besides being able to go louder, would be tighter, and have more low end than the Ace.
the added headroom on the deuce makes quite a difference to me...and the first time i switched into it through my 4x12 i was very suprised at how different it really did sound than the Ace. The Ace, TO ME, is bright, but the Deuce i have sounded pretty **** close to my Rectifier when i added gain in Tite or Fluid drive. I was able to use the EQ more effectively, and haven't stopped jammin away on the Stiletto since. we played all night last night and all day today. where as in the Ace, i was tending to use Bold and Silicone Diode, i find i like Spongy and Tube tracking on the Deuce better. and this is with everything STOCK. I played Tube chess with the Ace...finally ending up with the 450's. I will need to get a new set from Mesa to place in the Deuce now to see the difference again.

The Ace IS a great amp. It is extremely loud and has good tone. It was also my very first real Combo amp.

but I am kind of glad i went out and picked up this Deuce II. I think it might suit me and the rest of my gear better, since i have so many different options already.

 

[mightywarlock]

so you're using the same one that hollywood fixed, no issues yet???

not fixed yet.

i am still waiting for the previous owner to get me the receipt so i can warranty it. once i get that, i will transfer it into my name so i can get it looked at.
then i am selling it. i like the Deuce better for my needs.
but i still think the Ace is a great amp.

 

[ursinus]

Guess what? Tonight I was playing my MKIV since I have been neglecting it for a while and I blew a tube. I didn't feel like opening it up to inspect or change tubes, but tomorrow I'll check it out. Meanwhile, back to the Ace rig..... :shock:

 

[Billy Hiwatt]

MightyWarlock,
I scored a Lonestar head off Ebay, had a problem with it, and also
took it to Mesa Hollywood. They were not bothered at all by that.
Of course, I have purchased other items there, like a Grosh guitar,
and a bass rig.
I'm sure John will figure it out and get you back up to speed. They are
there to help...and sell, of course.

 

[mightywarlock]

ok, was looking at one of Rabies posts about his bad Deuce and saw the shot of the screen resistors.

so i got curious and pulled apart the ace again and unscrewed the tube board as best i could to see the "Dale's" and look what i saw...

now does this mean that BOTH TUBES failed???

can the Ace not handle the STR-450's i had just put in there??

am I correct in assuming both those ends need to be soldered there?

if so, couldn't i just resolder them and be done with it?

if someone knows, please get back to soon, so i know what to do.

the guy I bought it from still has not come through or returned my calls about the original receipt, so i am basically stuck either paying Mesa Hollywood to fix it for like $70 or just re-soldering these back on my own (doesn't look all that difficult if that's all that is needed).
if you can help, please let me know!
thanks!

 

[ursinus]

When grid resistors blow, it does not mean that the amp can't handle this or that tube. You have to remember that when a tube fails, it can send high voltage and/or high current to parts of the circuit that are not designed to handle them. Also, you can't just solder the grid resistor back to the board. If it got hot enough to unsolder itself, it definitely needs replacing. I know it is a pain, but get it serviced by a qualified tech. FWIW I have seen every brand of tube amp blow grid resistors from time to time.

 

[mightywarlock]

ok.
but does this mean that both brand new str450 tubes blew?
i know tubes can be bad from the start, but BOTH of them? i had them in the amp for 3 days, and when the amp died out, i was at band practice, and the amp had been on for about 2.5 hours...and it failed during the last song we were doing.

i am just trying to figure out whether i need to bring these tubes back to the mesa store or if it is some other issue.

 

[AdmiralB]

When did they stop chassis-mounting power tubes?

 

[ursinus]

ok.
but does this mean that both brand new str450 tubes blew?
i know tubes can be bad from the start, but BOTH of them? i had them in the amp for 3 days, and when the amp died out, i was at band practice, and the amp had been on for about 2.5 hours...and it failed during the last song we were doing.

i am just trying to figure out whether i need to bring these tubes back to the mesa store or if it is some other issue.

Usually, only one tube blows, but the extra surge was probably fed to the other tube also. It is much safer to replace both. BTW, I use 450's in my Stilletto Ace too. Love those tubes. The Str447's seem really fragile. That's what I blew in my MKIV head. Thankfully, no other damage was done except to blow a fuse.

If you have a recipt, you should be able to get replacements for your STR450's if they are that new.....

 

[AdmiralB]

Screen failures aren't caused by surges. They're usually caused by bad tubes (most common), followed by mismatched loads. If you run a higher numerical load than the amp wants (say, plugging a 16 ohm cab into the 4 ohm jack), the screen supply looks like a lower impedance to the amp and the screens start conducting.

The odds of two tubes with bad screen alignment at the same time seem remote.

Could well be a transformer problem. Could also be a PCB issue (ultrasonic oscillation).

 

[Jak0lantern01]

You know, in light of all the damage a bad tube can cause, why doesn't Mesa put some protective circuitry in their amps? A lot of high end amp makers now appear to be adding features where if a tube fails, the circuit cuts out and not only protects the amp, but also allows you to continue playing. Nice feature, eh?

 

[AdmiralB]

Mesa apparently doesn't believe in protection. They don't even fit HT fuses to most of their amps.

I've repaired two DRs that arced tube sockets, and caused resistors in the heater supplies to literally go up in flames - requiring PCB surgery.

Not only would HT fuses have prevented it, they used carbon comp resistors in these positions - the ONLY place in the amp that uses them, and they are the ONLY resistors that will burn! Talk about the wrong parts for the job.

 

[Charlie]

When did they stop chassis-mounting power tubes?

+1

At least they seem to be putting them on a separate PCB board... but I wish they would start chassis mounting them again. It may take several decades but that PCB is going to grow brittle over time... don't you think?

 

[recto-robbie]

God all mighty, I hope you guys start having better luck with your stilettos soon. I havent read any threads about stiletto problems since Rabies issues a while back and now I see this. This sucks.
Anyways I hope to add some optimism here. I havent used a Mesa tube in my Deuce since the first week I bought it and ive been playing this bad boy just about every night for about 2 hours straight since I bought it back in May. Not an issue ever, and for some **** reason it keeps sounding better. Maybe my cabs breaking in more.
Good luck to all of you.

 

[amused]

@Mighty Warlock

This is exactly what happened with mine - both resistors disconnected.
When I took it to the Boogie Store John soldered 2 new resistors to the opposite side of the circuit board so that they would be on top when chassis is inverted in combo.
I opted to replace the power tubes this monday, the ones that were in there were STR447, I replaced them with STR450 and I do like the sound a whole lot better, thanks. I would replace those 450's if you have the option without question - John told me that all of my problems with this stiletto were bad tubes (and they have had a lot of problems with the current batch of STR447.) Hope this helps.

 

[mightywarlock]

just dropped it off at the mesa store.

will get it back in a few days.

 

[mightywarlock]

well, John @ Mesa Hollywood hooked me up today. So I'll forgive his pissy attitude this time hehe...

Dropped it off first thing this morning, and he had it all set to go today by like 3pm.
no charge.
he mounted the screen grid resistors so they are on Top, and so this problem of them becoming unsoldered because they are hanging upside down wouldn't happen again.

also used new ones with a much longer lead to keep them further away from the tubes.
said my tubes were ok, i was just pushing too much power (about halfway on the master), and showed me on the scopes how 3/4 to halfway is where the power hits the max output. more than that you are just pushing the tubes into more gain territory.
kind of interesting to see it on the scope.
He also said this is like the 3rd one he has had to do, and that i should stick with the STR450's in there as the 447's(sovteks) are more unreliable then the seimens.
So i bought another set so i can use the 450's in the Deuce II as well, just have to mix them now, as i got a yellow the first time and they were all out, so i now have a yellow and a Green.

I am now going to call this a Mesa Hollywood Modded Ace.

heh...

next up, i'll do a video comparing the Ace to the Deuce, with the exact same settings and maybe different Tube choices as well.

All in all, i take this as an extreme lesson learned, at first disappointing, but I did learn more about this amp...and that's a good thing i believe.

8)

 

[mightywarlock]

:?

So i just got done A/B'ing the Ace and the Deuce and i am a little unsure now which i like better.

Here's what i did...I first played the Ace with the Combo speaker. it is Loud, and CLEAR, which i think we perceive as Trebly. I then played the Ace through the Recto 2x12. More low end, slightly scooped sound, not as clear as the combo speaker...still more trebly than the Deuce, and seemed not as much gain with exact same settings.
next, Deuce into 2x12 with exact same settings, spongy, tube, 50w.
lot's of low end, nice distortion, not as clear as the Ace. I can play sloppy with the Deuce. The Ace is so clear, you can't play sloppy or it accentuates your sloppyness.
back and forth i went...the Deuce has more low end for sure...and more angry distortion. These 2 amps are so similar, but the Ace definitely sounds different, as i have said before. But it being so Trebly, or just Clear, while having almost the same grunt was kind of surpising to me.

I was all set to post the Ace for sale tonight...

but now i'm not so sure.

I need much more A/B and play testing time, and with the band to see which is better.

I am thinking the Deuce, but now i dunno...


:shock:

 

[AdmiralB]

said my tubes were ok, i was just pushing too much power (about halfway on the master

This is BS. They build an amp you can't dime? Marshall would have been out of business by 1966 if that were true for them.

 

[Charlie]

said my tubes were ok, i was just pushing too much power (about halfway on the master

This is BS. They build an amp you can't dime? Marshall would have been out of business by 1966 if that were true for them.

Turning the amp up halfway definitely should not be a problem. Mesa has plenty of settings in the manual for the Stiletto with it turned up halfway on the master.

Kind of weird seeing so many of these problems with the Stiletto.